This section provides background information related to the present disclosure which is not necessarily prior art.
Fastening tools, such as power nailers have become relatively common place in the construction industry. Pneumatically-powered nailers, which are connected to an air compressor via an air hose, and powder nailers, which employ a powder fuel source that is rapidly combusted to produce a volume of pressurized gas, initially dominated the market. Both products, however, suffer from several drawbacks.
Pneumatically powered nailers require a relatively expensive air compressor that can be relatively cumbersome to transport. Additionally, it can be inconvenient to operate the nailer while it is tethered (via the air hose) to the air compressor. Many of the nailers powered by a powder fuel source are of the “single shot” variety and require significant effort to reload. Additionally, nailers employing a powder fuel source can be relatively noisy and can produce unpleasant odors during their operation.
Despite these limitations, pneumatic and powder-powered nailers continue to predominate for those construction applications, such as steel framing and concrete construction, which employ fasteners requiring a high degree of power to install the fasteners. Hence, while cordless electric nailers have become very successful for use in conventional wood construction (i.e., framing and trimming), cordless electric power nailers of this type are presently not suitable for use in steel framing or concrete construction applications.
Cordless electric powered nailers typically use springs to return the nail driver of the tool to its home position. A cordless electric powered nailer that is capable of installing concrete fasteners, including the installation of hardened fasteners through steel framing into concrete, must impart a significant amount of energy to the concrete fastener. Such driver return springs are prone to failure when subjected to the energy required to drive concrete fasteners. Accordingly, a much more robust and capable driver return mechanism is desired to improve the reliability of cordless electric powered nailers, including those capable of installing concrete fasteners.